The protective role of caffeic acid phenethyl ester (CAPE) on testicular tissue after testicular torsion and detorsion

Recent progresses in the pharmacological activities of caffeic acid phenethyl ester

The past decades have seen a growing interest in natural products. Caffeic acid phenethyl ester (CAPE), a flavonoid isolated from honeybee propolis, has shown multiple pharmacological potentials, including anti-cancer, anti-inflammatory, antioxidant, antibacterial, antifungal, and protective effects on nervous systems and multiple organs, since it was found as a potent nuclear factor κB (NF-κB) inhibitor. This review summarizes the advances in these beneficial effects of CAPE, as well as the underlying mechanisms, and proposes that CAPE offers an opportunity for developing therapeutics in multiple diseases. However, clinical trials on CAPE are necessary and encouraged to obtain certain clinically relevant conclusions.

Protective effects of apigenin on altered lipid peroxidation, inflammation, and antioxidant factors in methotrexate-induced hepatotoxicity

Methotrexate (MTX) is used as an effective chemotherapeutic agent against autoimmune diseases and tumors. Oxidative stress and inflammation are involved in the pathogenesis of MTX-induced damage. This study aimed at examining the ameliorating effects of apigenin (API) as a natural antioxidant on MTX-induced hepatotoxicity. The rats were classified into four groups: group I: normal saline-treated, group II: MTX-treated (20 mg/kg, ip, single dose at day 7), group III: MTX + API-treated (20 mg/kg, po), and group IV: API-treated. API was administrated for 9 days. Alanine aminotransferase (ALT), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) were used as biochemical factors of MTX-induced hepatic injury. In hepatic tissues, the levels of malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), and activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) as oxidative stress markers along with inflammatory factors such as tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β) were assessed. Our results showed that MTX administration significantly increased ALP, ASP, ALT, MDA, NO, TNF-α, and IL-1β levels and significantly decreased antioxidant factors such as GSH, CAT, GPx, and SOD. The API pretreatment group showed a significant rise in hepatic antioxidant markers, besides significant reductions in the serum levels of AST, ALT, and ALP and hepatic content of MDA, TNF-α, NO, and IL-1β. In addition, the hepatoprotective effect of API was confirmed by histological evaluation of the liver. API can prevent MTX-induced hepatotoxicity through mitigation of oxidative stress and inflammation.

Protective effects of Tadalafil and darbepoetin against ischemia - reperfusion injury in a rat testicular torsion model

Objectives:

To evaluate protective effects of darbepoetin and tadalafil against ischemia-reperfusion injury in ipsilateral and contralateral testicle.

Materials and Methods:

Thirty 3-month-old adult male Wistar-Albino rats were randomly divided into 5 groups (A-E). Sham operation was performed in the first group. In Group B, rats did not received any medication after creating 720 degrees torsion of the left testis. The rats in Group C, D and E received darbepoetin, tadalafil, and darbepoetin/tadalafil combination 30 minutes after creating 720 degrees torsion of the left testis, respectively. The testes of rats in these three groups were detorsioned at 90 minutes after drug administration. Both testes were removed at 30 minutes after detorsion.

Results:

There were significant differences between the groups in terms of the degree of histopathological damage, Johnsen score, fibrosis score and caspase-3 immunoreactivity in the torsioned testes (p: 0.000). The results for each parameter in the left testes were significantly better in the darbepoetin / tadalafil combination group. Similarly, there were also significant differences in the contralateral testes (p: 0.000).

Conclusion:

The active substances darbepoetin and tadalafil that were used as a combination had protective effects on both testes and produced out better results in preserving testicular histology. Especially in cases where it is not possible to rescue the torsioned testis, this result was more noticeable in the contralateral testis.

Hybrid caffeic acid derivatives as monoamine oxidases inhibitors: synthesis, radical scavenging activity, molecular docking studies and in silico ADMET analysis

BACKGROUND

Monoamine oxidase has been implicated in numerous neurological disorders. Although synthetic monoamine oxidase inhibitors (MAOI) have emerged with many side effects, the aspiration of natural based MAOI has greatly increased. As they exhibit fewer side effects and food interaction along with improved neuropharmacological profile.

RESULTS

The in silico design of the caffeic acid derivatives led potent MAO inhibitors with remarkable antioxidant activity. The mechanistic insight of the compounds within the hMAO active site was achieved by molecular docking which led us to be more confident of the possible inhibition of MAO.

CONCLUSIONS

The synthesized eugenol based ester of caffeic acid compound 7 exhibited MAO-A inhibition with IC₅₀ values of 07.03 ± 0.022 µM with good selectivity (SI = 0.291) towards MAO-A. Conversely, two anilides compounds 2 and 1, bearing chloro and nitro group at 2, 4 positions showed MAO-A inhibition with IC₅₀ values of 08.51 ± 0.017 µM and 08.87 ± 0.005 µM, respectively. Only one compound 5 was found as a significant MAO-B inhibitor with the IC₅₀ value of 10.80 ± 0.024 µM. Moreover, compounds 1, 2, 4 and 9 have profoundly appeared as potent antioxidants as evaluated in duel assay by scavenging DPPH and H₂O₂.

Protective effects of amifostine, curcumin and caffeic acid phenethyl ester against cisplatin-induced testis tissue damage in rats

Cisplatin is an effective antineoplastic drug that is usually used to treat a number of different types of cancer in the clinic. One of the most notable side effects of cisplatin use is infertility. The present study was designed to determine the non-oxidative testicular effects caused by the use of cisplatin in rats. The rats were randomly allocated to the experimental groups. The untreated rats represented the control group (group I) and the treatment groups were as follows: cisplatin alone (group II), cisplatin+amifostine (group III), cisplatin+curcumin (group IV), and cisplatin+caffeic acid phenethyl ester (CAPE; group V). The present study observed that following cisplatin administration, the expression of nuclear factor-κB (NF-κβ)/p65, caspase-3 and 8-deoxyguanosine (8-OHdG) increased in germinal epithelium and Leydig cells. However, the expression of these markers decreased in groups III–V, most notably in the group treated with amifostine. cisplatin induced-damage was countered by amifostine and curcumin. The results revealed that the activation of NF-κB, caspase-3 and 8-OHdG had a significant role in cisplatin-induced testicular toxicity. Thus, amifostine, curcumin and, to a lesser extent, CAPE have the potential for use as therapeutic adjuvants in cisplatin-induced testis injury.

Caffeic acid phenethyl ester protects against photothrombotic cortical ischemic injury in mice

In this study, we aimed to investigate the neuroprotective effects of caffeic acid phenethyl ester (CAPE), an active component of propolis purified from honeybee hives, on photothrombotic cortical ischemic injury in mice. Permanent focal ischemia was achieved in the medial frontal and somatosensory cortices of anesthetized male C57BL/6 mice by irradiation of the skull with cold light laser in combination with systemic administration of rose bengal. The animals were treated with CAPE (0.5–5 mg/kg, i.p.) twice 1 and 6 h after ischemic insult. CAPE significantly reduced the infarct size as well as the expression of tumor necrosis factor-α, hypoxiainducible factor-1α, monocyte chemoattractant protein-1, interleukin-1α, and indoleamine 2,3-dioxygenase in the cerebral cortex ipsilateral to the photothrombosis. Moreover, it induced an increase in heme oxygenase-1 immunoreactivity and interleukin-10 expression. These results suggest that CAPE exerts a remarkable neuroprotective effect on ischemic brain injury via its anti-inflammatory properties, thereby providing a benefit to the therapy of cerebral infarction.

Protective effects of hesperidin in experimental testicular ischemia/reperfusion injury in rats

INTRODUCTION

In this study, we aimed to determine the protective effects of hesperidin, a citrus flavonoid, in a model of testicular ischemia/reperfusion injury in rats.

MATERIAL AND METHODS

Forty-two pubertal male Wistar-Albino rats were divided into six groups: group 1 - control; group 2 - 50 mg/kg hesperidin (low dose hesperidin) used without torsion (LH group); group 3 - 100 mg/kg hesperidin without torsion (HH group); group 4 - torsion/detorsion group (T/D); group 5 - T/D + 50 mg/kg hesperidin treatment group (T/D + LH); and group 6 - T/D + 100 mg/kg hesperidin treatment group (T/D + HH). Hesperidin was given to the treatment groups 30 min before detorsion. After the fourth hour of reperfusion, orchiectomy was performed on the rats under anesthesia. The tissue samples were examined histologically and biochemically.

RESULTS

In the T/D group testicular malondialdehyde (MDA) levels were increased significantly (p < 0.001) whereas superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels were decreased compared to the control and other groups. However, hesperidin caused the effect of T/D to become closer to normal biochemical values. In addition, the histological examinations showed that T/D caused damage in the testis but hesperidin reduced this effect. The effects of hesperidin were found to be dose dependent. Thus, applying high doses would generate greater therapeutic effects.

CONCLUSIONS

In a rat testicular T/D model we observed biochemical and histological damage due to ischemia. However, high and low dose applications of hesperidin were shown to have protective effects against this damage. Therefore, the aforementioned citrus flavonoid may provide positive results in cases of testicular torsion.

Protective effect of pterostilbene on testicular ischemia/reperfusion injury in rats

PURPOSE

To evaluate protective effect of pterostilbene against testicular ischemia/reperfusion (I/R) injury, which results in increased formation of oxidative stress, leading to testicular apoptosis and impaired spermatogenesis.

METHODS

Thirty two pubertal male Sprague-Dawley rats weighing 180-220g were selected and randomly divided into the following four groups: group A (normal control group), group B (sham-operated group), group C (induced I/R injury group), group D (induced I/R injury group receiving pterostilbene treatment). Johnsen's scores and mean seminiferous tubule diameters were evaluated for histopathologic assessment; germinal cell apoptosis was evaluated by the transferase dUTP nick end labeling (TUNEL) assay and immunohistochemistry for caspases. Malondialdehyde (MDA) levels were assessed as an indicator of oxidative stress and total antioxidant capacity (TAC) was measured.

RESULTS

Germ cell apoptosis and MDA level significantly increased whereas TAC significantly decreased in group C; moreover, abnormal morphology and impaired spermatogenesis were observed in group C. In contrast, treatment with pterostilbene inhibited lipid peroxidation and apoptosis induced by ROS and restored the antioxidant capacity in group D.

CONCLUSIONS

These results show that treatment with pterostilbene may be a promising therapy for testicular I/R injury.

Mobile phone-induced myocardial oxidative stress: protection by a novel antioxidant agent caffeic acid phenethyl ester

Electromagnetic radiation (EMR) or radiofrequency fields of cellular mobile phones may affect biological systems by increasing free radicals, which appear mainly to enhance lipid peroxidation, and by changing the antioxidant defense systems of human tissues, thus leading to oxidative stress. Mobile phones are used in close proximity to the heart, therefore 900 MHz EMR emitting mobile phones may be absorbed by the heart. Caffeic acid phenethyl ester (CAPE), one of the major components of honeybee propolis, was recently found to be a potent free radical scavenger and antioxidant, and is used in folk medicine. The aim of this study was to examine 900 MHz mobile phone-induced oxidative stress that promotes production of reactive oxygen species (ROS) and the role of CAPE on myocardial tissue against possible oxidative damage in rats.

Thirty rats were used in the study. Animals were randomly grouped as follows: sham-operated control group (N: 10) and experimental groups: (a) group II: 900 MHz EMR exposed group (N: 10); and (b) group III: 900 MHz EMR exposed+CAPE-treated group (N: 10). A 900 MHz EMR radiation was applied to groups II and III 30 min/day, for 10 days using an experimental exposure device. Malondialdehyde (MDA, an index of lipid peroxidation), and nitric oxide (NO, a marker of oxidative stress) were used as markers of oxidative stress-induced heart impairment. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status. In the EMR exposed group, while tissue MDA and NO levels increased, SOD, CAT and GSH-Px activities were reduced. CAPE treatment in group III reversed these effects. In this study, the increased levels of MDA and NO and the decreased levels of myocardial SOD, CAT and GSH-Px activities demonstrate the role of oxidative mechanisms in 900 MHz mobile phone-induced heart tissue damage, and CAPE, via its free radical scavenging and antioxidant properties, ameliorates oxidative heart injury. These results show that CAPE exhibits a protective effect on mobile phone-induced and free radical mediated oxidative heart impairment in rats.

Anti-Apoptotic and Anti-Oxidant Effects of Caffeic Acid Phenethyl Ester on Cadmium-Induced Testicular Toxicity in Rats

Cadmium (Cd) is a serious environmental and occupational contaminant and may represent a serious health hazard to humans and other animals. Cd is reported to induce the generation of reactive oxygen species, and induces testicular damage in many species of animals. The goal of our study was to examine the anti-apoptotic and anti-oxidant effects of caffeic acid phenethyl ester (CAPE) on Cd-induced oxidative stress, apoptosis, and testicular injury in rats. A total of 40 male Wistar albino rats were divided into four groups: control, CAPE alone, Cd-treated, and Cd-treated with CAPE; each group consisted of 10 animals. To induce toxicity, Cd (1 mg/kg body weight) was dissolved in normal saline and subcutaneously injected into rats for 30 days. The rats in CAPE-treated group were given a daily dose of 10 μmol/kg body weight of CAPE by using intraperitoneal injection. This application was continued daily for a total of 30 days. To date, no examinations of the anti-apoptotic and anti-oxidant properties of CAPE on Cd-induced apoptosis, oxidative damage, and testicular injury in rat testes have been reported. CAPE-treated animals showed an improved histological appearance and serum testosterone levels in Cd-treated group. Our data indicate a significant reduction in the number of apoptotic cells in testis tissues of the Cd-treated group with CAPE treatment. Moreover, CAPE significantly suppressed lipid peroxidation, compensated deficits in the anti-oxidant defenses in testes tissue resulted from Cd administration. These findings suggest that the protective potential of CAPE in Cd toxicity might be due to its anti-oxidant and anti-apoptotic properties, which could be useful for achieving optimum effects in Cd-induced testicular injury.

Effects of intralipid and caffeic acid phenyl esther (CAPE) against hepatotoxicity and nephrotoxicity caused by glyphosate isopropylamine (GI)

This study was aimed to investigate the protective effects of caffeic acid phenyl esther (CAPE) and Intralipid (IL) against hepatotoxicity and nephrotoxicity caused by acute intoxication of glyphosate (N-phosphonomethyl)glycine) (GI) in rats. Forty-nine Wistar Albino rats were randomly divided into seven groups as: I, Control; II, Intralipid (IL) (18.6 mL/kg, orally); III, CAPE (10 µmol/kg, intraperitoneally); IV, GI (4 mg/kg/day, intraperitoneally); V, GI + IL; VI, GI+CAPE; and VII, GI + IL + CAPE. Total antioxidant status (TAS) and total oxidant status (TOS) levels were measured in serum samples. Tissues were analyzed with hematoxylin and eosin (H&E) staining protocol. Bcl-2, Bax, and caspase-3 were evaluated by immunohistochemical method. The results revealed that, in hepatic tissues, the TAS levels were lower and the TOS levels were higher in the GI group compared to other groups. In renal tissues, the TAS levels were significantly lower in the GI group than in the control, IL, CAPE, and GI + IL + CAPE groups. The TOS levels were significantly higher in the GI group than in the control group. Moreover, histopathological analysis revealed severe hepatotoxicity in the GI group. In the GI + CAPE + IL group, hepatotoxicity recovered significantly. Nephrotoxicity was also observed in the GI group and moderately reduced in the GI + CAPE group. Biochemical results were confirmed by histopathologic examination. The results also revealed that CAPE and IL, due to their antioxidant effects, have a decreasing effect against both hepatotoxicity and nephrotoxicity caused by GI. Therefore, CAPE and IL may function as potential agents for supportive therapy since they decrease organ damage, or may facilitate the therapeutic effects of the routine treatment of patients with GI poisoning.

The role of CAPE in PI3K/AKT/mTOR activation and oxidative stress on testis torsion

Ischemia reperfusion injury arises from testicular torsion resulting in a loss of spermatogenesis and significant germ cell apoptosis. This study evaluates the prooxidant/antioxidant effects of caffeic acid phenethyl ester (CAPE) through PI3K/AKT/mTOR signal pathways on testis torsion. A total of (28) male Wistar rats were divided randomly into 4 groups (n=7 for each group):group A (sham) group,group B torsion/detorsion group, group C (saturation group, during four days of CAPE, one dose (10 μmol/kg, i.p)) and group D (a single dose of CAPE 2h after torsion and before detorsion). At the end of the study, unilateral orchiectomies were performed for measurements of MDA and 8OHdG levels, histopathologic and immunohistochemical and TUNEL apoptotic cell examination. Testicular torsion-detorsion led to a significant decrease in the mean values of the Johnsen's scores and a significant increase in the apoptotic cell values of group B. There were no significant differences between group D and group A. In addition, the MDA and 8OHdG levels increased significantly in group B. The MDA and 8OHdG values were lower in group D. However, the 8OHdG levels were higher in group C than the groups A and D. On the other hand, CAPE suppresses mTOR activation and reduces the apoptosis on ischemia/reperfusion damage in rat testis. These results demonstrate that CAPE suppresses mTOR activation and reduces the apoptosis on ischemia/reperfusion damage in rat testis.

Pre-administration of turmeric prevents methotrexate-induced liver toxicity and oxidative stress

BACKGROUND

Methotrexate (MTX) is an antimetabolite broadly used in treatment of cancer and autoimmune diseases. MTX-induced hepatotoxicity limits its application. We investigated hepatoprotective effects of turmeric in MTX-induced liver toxicity.

METHODS

All experiments were performed on male Wistar albino rats that were randomly divided into six groups. Group one received saline orally for 30 days (control group), groups two and three received turmeric extract (100, 200 mg/kg respectively) orally for 30 days, group four received single dose, of MTX IP at day 30, groups five and six received turmeric extract 100 and 200 mg/kg orally respectively for 30 days and single dose of methoterxate IP (20 mg/kg) at day 30. Four days after MTX injection animals were sacrificed and evaluated. Blood ALT and AST (indicators of hepatocyte injury), ALP and bilirubin (markers of biliary function), albumin (reflect liver synthetic function) as well as the plasma TAS concentration (antioxidant defenses) were determined. The cellular antioxidant defense activities were examined in liver tissue samples using SOD, CAT, and GSH-Px for the oxidative stress, and MDA for lipid peroxidation. In addition, liver damage was evaluated histopathologically.

RESULTS

MTX significantly induced liver damage (P<0.05) and decreased its antioxidant capacity, while turmeric was hepatoprotective. Liver tissue microscopic evaluation showed that MTX treatment induced severe centrilobular and periportal degeneration, hyperemia of portal vein, increased artery inflammatory cells infiltration and necrosis, while all of histopathological changes were attenuated by turmeric (200 mg/kg).

CONCLUSION

Turmeric extract can successfully attenuate MTX-hepatotoxicity. The effect is partly mediated through extract's antinflammatory activity.

Melatonin attenuates lung injury in a hind limb ischemia-reperfusion rat model

OBJECTIVE

This study evaluated the protective antioxidant effect of melatonin on lung injury as a remote organ after skeletal muscle ischemia-reperfusion in rats.

METHODS

Thirty male Wistar rats were allocated randomly into three experimental groups: operated with no ischemia (Sham) group, ischemia-reperfusion group and ischemia-reperfusion+melatonin group. Hind limb ischemia was induced by clamping the femoral artery. After 2h ischemia, the clamp was removed and the animal underwent 24h reperfusion. Rats in the ischemia-reperfusion + melatonin group received melatonin (10 mg/kg i.v.), immediately before the clamp was removed. At the end of the trial, animals were euthanized and the lungs were removed for water content determination, histopathological and biochemical studies.

RESULTS

In the ischemia-reperfusion + melatonin group, tissues showed less intense histological abnormalities such as neutrophilic infiltration, intra-alveolar hemorrhage and edema compared with the ischemia-reperfusion group. Histopathologically, there was a significant difference (P < 0.05) between the two groups. The lung water content in the ischemia-reperfusion + melatonin group was significantly lower than the ischemia-reperfusion group (P < 0.05). Lung tissue myeloperoxidase (MPO) activity and nitric oxide (NO) level were significantly (P < 0.05) increased by ischemia-reperfusion. The increase in these parameters was reduced by melatonin. Comparing the ischemia-reperfusion+melatonin group with the sham group, no significant increase in all analyzed aspects of the research was observed.

CONCLUSIONS

These findings suggest that melatonin has preventive effects in lung tissue injury after transient femoral artery occlusion.

The biochemical effects of ischemia-reperfusion injury in the ipsilateral and contralateral testes of rats and the protective role of melatonin

Testicular torsion (TT) is a serious urologic emergency that is observed in adolescent males and that can lead to infertility if left untreated. The ischemia-reperfusion (I/R) injury due to TT has been implicated in the pathogenesis of testicular damage. We investigated the effects of melatonin on oxidative damage in the ipsilateral and contralateral testes of rats induced by unilateral TT. A total of 21 prepubertal male Wistar albino rats were divided into three groups, each consisting of seven rats. In Group 1 (SHAM group): a sham operation to the left testis and bilateral orchiectomy were performed. In Group 2 (I/R group): I/R injury was created by rotating the left testis 720° in a clockwise direction for 2 h and detorsing the testis after 2 h. Group 3 (I/R + MEL group): rats were subjected to I/R injury and one-shot melatonin injection (50 mg kg⁻¹, intraperitoneal (i.p.)). The testes of the rats were excised bilaterally in all groups. The testicular tissue activities of antioxidant catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase enzymes (GSH-Px), and the tissue levels of malondialdehyde (MDA), protein carbonyl (PC) and nitric oxide (NO) were determined. Administration of melatonin caused a significant decrease in lipid peroxidation and enzyme activities in the ipsilateral testis when compared with the control group (P < 0.05). All of the changes in the enzyme activities of the contralateral testis were insignificant (P > 0.05). MDA levels were significantly altered in the contralateral testis (P = 0.009). Melatonin administration decreased the deleterious effects of I/R injury in the ipsilateral torted testes of the rats. The contralateral testes were slightly affected by unilateral TT.

The effects of carvedilol on ischemia-reperfusion injury in the rat testis

OBJECTIVE

To analyze the oxidative damage and histopathological alterations caused by ischemia-reperfusion (I/R) injury and ameliorative effects of carvedilol (CVD) in the rat testis.

MATERIALS AND METHODS

Twenty-one male rats were randomized into 3 groups as follows: Group I (n = 7); control (sham) group, Group II (n = 7); I/R group, in which I/R injury was performed by torsing the left testis 720 ° clockwise for 2 hours and detorsing for 2 hours. Group III (n = 7); CVD treatment group; in addition to I/R process, one-dose of CVD was administered (2mg/kg, i.p) 30 min. before detorsion. Levels of antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and levels of malondialdehyde (MDA) and protein carbonyl (PC) were determined in testicular tissues and serum of rats. Testicular tissues were also examined histopathologically and Johnsen scores were determined.

RESULTS

Activities of SOD and GSH-Px in serum and testicular tissues were increased by I/R, but administration of CVD decreased these levels (p < 0.001 and p = 0.001). Significantly increased MDA levels in serum and testicular tissues were decreased by CVD treatment (p < 0.001 and p = 0.001). Concerning PC levels in serum and testicular tissues, there was no statistically significant difference between the groups (p = 0.989 and p = 0.428). There was not a statistically significant difference in terms of mean Johnsen scores between the groups (p = 0.161).

CONCLUSIONS

Administration of CVD decreased oxidative damage biochemically in the rat testis caused by I/R injury, but histopathologically no change was observed betwe¬en all of the groups.

Caffeic acid phenethyl ester as a protective agent against nephrotoxicity and/or oxidative kidney damage: a detailed systematic review

Caffeic acid phenethyl ester (CAPE), an active component of propolis, has been attracting the attention of different medical and pharmaceutical disciplines in recent years because of its antioxidant, anti-inflammatory, antiproliferative, cytotoxic, antiviral, antifungal, and antineoplastic properties. One of the most studied organs for the effects of CAPE is the kidney, particularly in the capacity of this ester to decrease the nephrotoxicity induced by several drugs and the oxidative injury after ischemia/reperfusion (I/R). In this review, we summarized and critically evaluated the current knowledge regarding the protective effect of CAPE in nephrotoxicity induced by several special medicines such as cisplatin, doxorubicin, cyclosporine, gentamycin, methotrexate, and other causes leading to oxidative renal injury, namely, I/R models and senility.

Caffeic acid phenethyl ester and therapeutic potentials

Caffeic acid phenethyl ester (CAPE) is a bioactive compound of propolis extract. The literature search elaborates that CAPE possesses antimicrobial, antioxidant, anti-inflammatory, and cytotoxic properties. The principal objective of this review article is to sum up and critically assess the existing data about therapeutic effects of CAPE in different disorders. The findings elaborate that CAPE is a versatile therapeutically active polyphenol and an effective adjuvant of chemotherapy for enhancing therapeutic efficacy and diminishing chemotherapy-induced toxicities.

WITHDRAWN: Melatonin attenuates lung injury in a hind limb ischemia-reperfusion rat model

This article has been withdrawn for editorial reasons because the journal will be published only in English. In order to avoid duplicated records, this article can be found at http://dx.doi.org/10.1016/j.rppnen.2014.01.010. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Resveratrol ameliorates methotrexate-induced hepatotoxicity in rats via inhibition of lipid peroxidation

Hepatotoxicity is one of the major complications of methotrexate (MTX) therapy. This study was carried out to evaluate the possible protective effect of resveratrol (trans-3,5,4'-trihydroxystilbene, RVT) against MTX-induced hepatotoxicity. Rats were randomly divided into four groups as control, MTX treated (7 mg/kg/day, intraperitoneally (i.p.), once daily for 3 consecutive days), MTX + RVT treated (20 mg/kg/day, i.p.), and RVT treated. First dose of RVT was administrated 3 days before the MTX injection and continued for 3 days. Histopathology of liver was evaluated by light microscopy. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) were used as biochemical markers of MTX-induced hepatic injury. The levels of thiobarbituric acid reactive substances (TBARS, a marker of lipid peroxidation) and activities of hepatic antioxidant enzymes such as catalase (CAT) and glutathione-S-transferase (GST) were used to analyze the oxidative stress-mediated lipid peroxidation in liver sections. Our results showed that MTX administration significantly increased ALT, ASP, and ALP levels. TBARS, CAT, and GST levels were also markedly increased in liver after MTX administration. RVT treatment significantly prevented MTX-induced hepatotoxicity, as indicated by AST, ALT, and ALP levels and liver histopathology. Moreover, administration of RVT significantly decreased the elevated levels of TBARS and activities of CAT and GST in the liver compared to MTX-treated group. These results revealed that RVT may have a protective effect against MTX-induced hepatotoxicity by inhibiting oxidative stress-mediated lipid peroxidation. Consequently, RVT treatment might be a promising strategy against MTX-induced hepatotoxicity.

Mechanism of acute lung injury due to phosgene exposition and its protection by cafeic acid phenethyl ester in the rat

The mechanism of phosgene-induced acute lung injury (ALI) remains unclear and it is still lack of effective treatments. Previous study indicated that oxidative stress was involved in phosgene-induced ALI. Caffeic acid phenethyl ester (CAPE) has been proved to be an anti-inflammatory agent and a potent free radical scavenger. The purpose of this study was to investigate the protective effects of CAPE on phosgene-induced ALI and identify the mechanism, in which oxidative stress and inflammation were involved. The phosgene was used to induce ALI in rats. The results showed that after phosgene exposure, total protein content in BALF was not significantly changed. The increase of MDA level and SOD activity induced by phosgene was significantly reduced by CAPE administration, and the decrease of GSH level in BALF and lung were significantly reversed by CAPE. CAPE also partially blocked the translocation of NF-κB p65 to the nucleus, but it had little effect on the phosphorylation of p38 MAPK. In conclusion, CAPE showed protective effects on lung against phosgene-induced ALI, which may be related with a combination of the antioxidant and anti-inflammatory functions of CAPE.

Effects of caffeic acid phenethyl ester on endotoxin-induced cardiac stress in rats: a possible mechanism of protection

Endotoxins (lipopolysaccharides; LPS) are known to cause multiple organ failure, including myocardial dysfunction. The present study aimed to investigate the mechanism of caffeic acid phenethyl ester (CAPE) protection against LPS-induced cardiac stress. Rats were allocated into three groups; group 1 served as a normal control group, group 2 (LPS) received a single intraperitoneal injection of LPS (10 mg/kg), group 3 (LPS + CAPE) was injected intraperitoneally with CAPE (10 mg/kg/day; solubilized in saline containing 20% tween 20) throughout a period of 10 days prior to LPS injection. Rats were maintained 4 h before sacrifice. Caffeic acid phenethyl ester pretreatment normalized LPS-enhanced activities of serum creatine kinase (CK) and lactate dehydrogenase (LDH) as well as glutathione peroxidase (GPx), and myeloperoxidase (MPO) in cardiac tissue. A significant reduction of the elevated levels of serum tumor necrosis factor-alpha (TNF-α) as well as serum and cardiac nitrite/nitrate (NOx) ) was achieved after CAPE pretreatment. CAPE also restored malondialdelyde (MDA), reduced glutathione (GSH), and cytosolic calcium (Ca2+ ) levels in the heart. A marked induction of cardiac heme oxygenase-1 (HO-1) protein level was detected in CAPE-pretreated group. Whereas, LPS-induced reduction of adenosine triphosphate (ATP) and phosphocreatine (PCr) levels was insignificantly changed. Conclusively, the early treatment with CAPE maintained antioxidant defences, reduced oxidative injury, cytokine damage, and inflammation but did not markedly improve energy status in cardiac tissue. The beneficial effect of CAPE might be mediated, at least in part, by the superinduction of HO-1.

The ultrastructural and biochemical evidences of the beneficial effects of chronic caffeic acid phenethyl ester and melatonin administration on brain and cerebellum of aged rats

Nervous system is highly vulnerable to the deleterious effects of age-related oxidative stress. A large body of researches has consistently confirmed the implication of free radicals both in normal cerebral ageing and ageing-related pathologies. In the present study, in addition to the light and electron microscopic pictures of brain and cerebellum of young, old and antioxidant administered old Sprague-Dawley rats, pro-oxidant status was evaluated in terms of measurements of total glutathione, lipid peroxidation (malondialdehyde) and activities of superoxide dismutase, catalase and glutathione peroxidase. Taking the results together, we suggest that supplemental administration of caffeic acid phenethyl ester and melatonin is beneficial in delaying age-related cellular damage in nervous system.

The protective effect of caffeic acid phenethyl ester (CAPE) on oxidative stress in rat liver exposed to the 900 MHz electromagnetic field

In this study, we aimed to investigate the possible protective effects of caffeic acid phenethyl ester (CAPE) on lipid peroxidation (LPO) and the activities of antioxidant enzymes in the liver of rats exposed to the 900 MHz electromagnetic field (EMF). EMF of cellular phones may affect biological systems by increasing free radical, which appear mainly to enhance LPO, and by changing the antioxidative activities of liver, thus leading to oxidative damage. CAPE, an active component of propolis extract, exhibits antioxidant properties and several studies suggest that supplementation with antioxidant can influence EMF exposure induced hepatotoxicity. Thirty male Sprague-Dawley rats were divided into three groups: control ( n = 10), 900 MHz EMF ( n = 10) and 900 MHz EMF + CAPE ( n = 10). CAPE was injected intraperitoneally for 30 days before exposure to EMF. Liver tissue was removed to study the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), xanthine oxidase (XO) and the levels of LPO. The activities of XO, CAT and level of LPO increased in the 900 MHz electromagnetic field (EMF) group compared with the control group, although XO, CAT activities and LPO levels were decreased by 900 MHz EMF + CAPE administration. The activities of SOD and GSH-Px decreased in the 900 MHz EMF group compared with the control group, although their levels were increased by EMF + CAPE administration. It can be concluded that CAPE may prevent the 900 MHz EMF-induced oxidative changes in liver by strengthening the antioxidant defense system by reducing reactive oxygen species and increasing antioxidant enzyme activities.

Protective role of natural antioxidant supplementation on testicular tissue after testicular torsion and detorsion

OBJECTIVES

To investigate the impact of garlic extract (GE), which is known for its antioxidant activity, on a testicular torsion/detorsion model in animals and to help understand how to prevent both ischemic and reperfusion injuries after testicular torsion and detorsion.

MATERIAL AND METHODS

Six groups of rats (n=7 in each group) were used. The animals in the control group (Group I) did not receive any treatment. The animals in the sham group (Group II) underwent scrotal incision and testicular fixation only. The animals in Groups III-VI underwent 720 degrees of left testicular torsion for 2 h; subsequent detorsion was performed for 2h in Groups IV and VI only. Animals in Groups V and VI were treated exactly the same as those in Groups III and IV, respectively except that they were pretreated with oral GE for 5 days at a dosage of 5 ml/kg. Both testicles in all rats were removed and tissue malondialdehyde (MDA) levels and enzymatic activities of xanthine oxidase (XO) were studied, in addition to a histological evaluation after hematoxylin-eosin staining.

RESULTS

Testicular MDA levels and XO activities were higher in Group III compared to Group II (p<0.05). Pretreatment with GE prevented these increases. Detorsion caused more damage and resulted in a further increase in MDA levels but MDA levels were not increased in animals pretreated with GE. Histologically, torsion caused some separation between germinative cells in the seminiferous tubules, which became much more prominent in Group IV and was attenuated by GE pretreatment. There were no significant changes in any of the above-mentioned enzymatic activities or histopathologic changes in the contralateral testicle in any of the groups.

CONCLUSIONS

We believe that both testicular torsion and detorsion result in testicular tissue damage by means of lipid peroxidation, which is evident by an increase in the tissue levels of MDA. Dietary supplementation with GE seems to attenuate the generation of toxic free radicals, as evidenced indirectly by low tissue MDA levels.

Caffeic acid phenethyl ester modulates methotrexate-induced oxidative stress in testes of rat

The aim of this study was to investigate the possible protective role of caffeic acid phenethyl ester on testicular toxicity of methotrexate in rats. Nineteen male rats were divided into three groups as follows: group I, control; group II, methotrexate-treated; group III, methotrexate + caffeic acid phenethyl ester-treated. In the second day of experiment, a single dose of methotrexate was intraperitoneally administered to groups II and III, although a daily single dose of caffeic acid phenethyl ester was intraperitoneally administered to group III for 7 days. At the end of the experiment, the testes of the animals were removed and weighed. In the tissue, the level of lipid peroxidation as malondialdehyde and activities of superoxide dismutase were higher in the methotrexate group than in the control group. Lipid peroxidation levels and superoxide dismutase activities were decreased in caffeic acid phenethyl ester + methotrexate group compared with methotrexate group. The activities of catalase in the methotrexate group decreased insignificantly although its activities were significantly increased by caffeic acid phenethyl ester administration. The activity of glutathione peroxidase did not change in the groups. There was significant difference in body weight between control and methotrexate-induced groups. In conclusion, the administration of methotrexate causes elevation of oxidative stress although treatment with caffeic acid phenethyl ester has protective effects on the oxidative stress in testes.

Protective effect of trapidil on long-term histologic damage in a rat model of testicular ischemia-reperfusion injury

OBJECTIVES

Trapidil is an antianginal compound with a broad spectrum of pharmacological activities. In recent years, it has been used successfully to decrease ischemia-reperfusion injury in several organ systems. We evaluated the effect of trapidil on the long-term histologic damage in testicular ischemia-reperfusion injury.

METHODS

Adult male Wistar rats were divided into three groups of six rats each. One group underwent 2 h of testicular torsion; one received pretreatment with trapidil before detorsion; and one group underwent sham operation. All rats underwent bilateral orchiectomy 60 days after the experiment. The mean seminiferous tubular diameter, germinal epithelial cell thickness, and mean testicular biopsy score were determined by histological examination of each testis.

RESULTS

Testicular torsion-detorsion caused a significant decrease in the mean seminiferous tubular diameter, germinal epithelial cell thickness, and mean testicular biopsy score in the ipsilateral testes, but not in the contralateral testes. The animals treated with trapidil had a significant increase in these histological parameters as compared to the torsion-detorsion group.

CONCLUSION

Trapidil administration before reperfusion may have the potential to decrease the long-term histologic damage that occurs after experimental testicular torsion. Trapidil is used as an antianginal drug and additional clinical studies are required to elucidate the protective role of trapidil in patients with testicular torsion.

Ethyl pyruvate reduces germ cell-specific apoptosis and oxidative stress in rat model of testicular torsion/detorsion

PURPOSE

Testicular torsion/detorsion (T/D) results in enhanced formation of free radical metabolites, which contributes to the pathophysiology of tissue damage. We investigated the protective effects of ethyl pyruvate (EP) against testis tissue damage in an experimental model of testicular torsion.

METHODS

Sprague-Dawley rats were divided into 5 groups. In those animals that underwent T/D, right testes were rotated 720 degrees for 1 hour. Group 1 control rats underwent sham operation. In group 2, the rats underwent T/D. The EP was prepared and injected in the form of Ringer's ethyl pyruvate solution. The rats in group 3, 4, and 5 received 2 doses of 20, 50, and 100 mg/kg EP (30 minutes before and after detorsion), respectively. The right testes of 6 animals from each group were excised 4 hours after detorsion for the measurement of lipid peroxidation, myeloperoxidase (MPO), and antioxidant enzymes activities. Germ cell apoptosis was determined in right testes of 8 animals per group 24 hours after detorsion. The epididymal sperm concentration and motility were evaluated 1 month after treatments.

RESULTS

Germ cell apoptosis indices were significantly higher in group 2 compared with control group. The level of lipid peroxidation and MPO activity increased, whereas antioxidant enzymes activities decreased after T/D. Sperm count and motility were also reduced 1 month after T/D in group 2 rats. However, EP treatment at doses of 50 and 100 mg/kg significantly decreased the early apoptotic damage and improved long-term sperm count and motility. In the same dosing groups, we observed normalization of oxidant/antioxidant balance and decrement of MPO activity. However, administration of 20 mg/kg of EP conferred no protective effect.

CONCLUSIONS

Administration of Ringer's ethyl pyruvate solution (in appropriate doses) is protective against apoptotic tissue damage following testicular torsion and improves long-term testicular function. The antioxidant and anti-inflammatory properties of EP seem responsible for the protective effects. Our findings suggest this resuscitation solution as a possible substitute for fluid and electrolyte maintenance during surgical detorsion.

Protective effect of L-carnitine on testicular ischaemia-reperfusion injury in rats

Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential.

CAPE (caffeic acid phenethyl ester) stimulates glucose uptake through AMPK (AMP-activated protein kinase) activation in skeletal muscle cells

Caffeic acid phenethyl ester (CAPE), a flavonoid-like compound, is one of the major components of honeybee propolis. In the present study, we investigated the metabolic effects of CAPE in skeletal muscle cells and found that CAPE stimulated glucose uptake in differentiated L6 rat myoblast cells and also activated AMPK (AMP-activated protein kinase). In addition, the inhibition of AMPK blocked CAPE-induced glucose uptake, and CAPE activated the Akt pathway in a PI3K (phosphoinositide 3-kinase)-dependent manner. Furthermore, CAPE enhanced both insulin-mediated Akt activation and glucose uptake. In summary, our results suggest that CAPE may have beneficial roles in glucose metabolism via stimulation of the AMPK pathway.

Dehydroepiandrosterone treatment attenuates reperfusion injury after testicular torsion and detorsion in rats

PURPOSE

We aimed to evaluate the effects of dehydroepiandrosterone (DHEA) on antioxidant enzyme activities, lipid peroxidation, and histopathologic changes in both testes after unilateral testicular torsion and detorsion.

METHODS

Twenty-four adult male Sprague-Dawley rats were randomly divided into 4 groups (n = 6 for each group): sham operation, torsion/detorsion (T/D), T/D + vehicle, and T/D + DHEA. Three hours before detorsion, 50 mg/kg DHEA was given intraperitoneally to the T/D + DHEA group. Testicular ischemia was achieved by twisting the left testis 720 degrees clockwise for 3 hours, and reperfusion was allowed for 24 hours after detorsion. In all groups, bilateral orchiectomies to determine the testicular tissue catalase (CAT) and superoxide dismutase activities and malondialdehyde (MDA) levels and histopathologic examination were performed.

RESULTS

Compared with those from the sham group, CAT activities in the ipsilateral testis obtained from the T/D group were significantly lower and MDA levels were significantly higher (P < .05 for all). Administration of DHEA prevented increases in MDA levels and decreases in CAT and superoxide dismutase activities when compared to the T/D group. Specimens from the T/D and the T/D + vehicle groups had a significantly greater histologic injury than the specimens from the sham and the T/D + DHEA groups had (P < .01 for both).

CONCLUSIONS

The results suggest that DHEA may be a protective agent for preventing biochemical and histopathologic changes related to oxidative stress in testicular injury caused by testis torsion.

Protective effect of caffeic acid phenethyl ester (CAPE) on fluoride-induced oxidative stress and apoptosis in rat endometrium

High fluoride intake may affect biological systems by increasing free radicals, which may enhance lipid peroxidation levels of the tissues, thus leading to oxidative damage. Caffeic acid phenethyl ester (CAPE), a component of honeybee propolis, protects tissues from reactive oxygen species mediated oxidative stress in ischemia-reperfusion and toxic injuries. Several studies suggest that supplementation with anti-oxidant can influence fluoride induced tissue damage. The aims of this study was to investigate the possible role of malondialdehyde (MDA) levels and activity of superoxide dismutase (SOD) and catalase (CAT), in the pathogenesis of fluoride-induced endometrial damage and to demonstrate the effect of CAPE, the potent antioxidant, in decreasing the toxicity. Twenty-four adult female rats were randomly divided into three experimental groups, as follows: control group, fluoride-treated group (F), and fluoride plus CAPE-treated group (F+CAPE). Fluoride was given orally as 30mg/L NaF solution in spring water daily for 45 days. CAPE was co-administered intraperitoneally (i.p.) with a dose of 10μM/(kgday) for 46 days. Extensive formation of DNA strand breaks, the typical biochemical feature of apoptosis, was detected with the use of the terminal deoxynucleotidyl transferase (TdT)-mediated d UTP-biotin nick and labeling (TUNEL) method. The activities of antioxidant enzymes such as SOD and CAT as well as the concentration of MDA, as an indicator of lipid peroxidation, were measured to evaluate oxidative stress in homogenates of the endometrium. Fluoride administration increased MDA levels (p<0.05), decreased SOD (p<0.05) and CAT (p<0.05) activities. CAPE co-administration with fluoride treatments caused significantly decreased MDA levels (p<0.05), increased SOD (p<0.05) and CAT (p<0.05) activities in endometrial tissue when compared with F alone. Diffuse apoptosis in glandular epithelium and stromal cells was found by TUNEL method in endometrial tissues of rats treated with fluoride. The severity of these lesions was reduced by administration of CAPE. In conclusion, our study demonstrated that MDA may play an important role in the pathogenesis of fluoride-induced oxidative endometrial damage. CAPE may have protective aspects in this process by its antioxidant and anti-inflammatory effect.

A preliminary study of the levels of testis oxidative stress parameters after MK-801-induced experimental psychosis model: protective effects of CAPE

We evaluated the effects of caffeic acid phenethyl ester (CAPE) on antioxidant enzyme levels and histopathologic changes in dizocilpine (MK-801) induced schizophrenic rat testis. A total of 30 adult male Wistar-Albino rats were divided into three groups. Group-I was used as control. Rats in the Group-II were intraperitoneally injected with MK-801, whereas those in Group-III were intraperitoneally injected with CAPE in addition to MK-801. The testes were collected for biochemical and histopathological examinations. Antioxidant enzyme activities, malondialdehyde, protein carbonyl and nitric oxide levels in testicular tissues were analyzed with spectrophotometric methods. Induction of schizophrenia resulted in a significant oxidative stress by increasing the levels of antioxidant enzymes. Tissue malondialdehyde and protein carbonyl levels were also increased. Treatment with CAPE led to significant decrease in oxidative injury. Administration of CAPE reduced the detrimental histopathologic changes caused by MK-801. The results showed that experimentally induced schizophrenia caused oxidative stress in testes of rats and treatment with CAPE reduced these harmful effects.

Caffeic acid phenethyl ester prevents cadmium-induced cardiac impairment in rat

Caffeic acid phenethyl ester (CAPE), a flavonoid like compound, is one of the major components of honeybee propolis. It was found to be a potent free radical scavenger and antioxidant recently. The aim of this study was to examine the effect of CAPE on cadmium (Cd)-induced hypertension and cardiomyopathy in rats. In particular, nitric oxide (NO) may contribute to the pathophysiology of Cd induced cardiac impairment. Malondialdehyde (MDA, an index of lipid peroxidation) levels and nitric oxide (NO, a vasodilator) levels were used as markers Cd-induced cardiac impairment and the success of CAPE treatment. Also, the findings have been supported by the histopathologic evidences. The rats were randomly divided into three experimental groups each (12), as follows: the control group, Cd-treated group (Cd) and Cd plus CAPE-treated group (Cd+CAPE). CdCl(2) in 0.9% NaCl was administrated intraperitoneally (i.p.) with a dose of 1mg/kg/day. CAPE was co-administered i.p. a dose of 10 microM/kg for 15 days. Hypertension was found to be induced by intraperitoneal administration of Cd in a dose of 1mg/kg/day on the measurements taken 15 days later. MDA levels were increased (p<0.001) in cardiac tissue and NO levels were decreased (p<0.05) in serum in the Cd group than those of the control group had. On the other hand, there was a slight difference (increase) in MDA levels in the Cd+CAPE group than the ones in the control group (p<0.003). In addition, MDA levels were decreased and NO levels were increased in the Cd+CAPE group compared with the Cd group (p<0.001, p<0.0001, respectively). As a result, treatment with CAPE significantly reversed the increased lipid peroxidation (LPO) product, MDA, and decreased NO levels in Cd treated animals. In the histopathologic examination, a significant hypertrophy in atrial and ventricular myofibrils was observed in only Cd administered group, in comparison with the control group. There was no statistically significant difference between the CAPE given and control groups by means of atrial and ventricular myofibril diameters. In conclusion, the underlying mechanism of the myocardial hypertrophy may be related to hypertension due to inhibition of NO production in the vessels, and CAPE has a protective effect on Cd-induced hypertension mediated cardiac impairment in the rats.

The effect of caffeic acid phenethyl ester (CAPE) on histopathological changes in testicular ischemia-reperfusion injury

Testicular torsion causes an enhanced formation of reactive oxygen species which contributes to the pathophysiology of ischemia-reperfusion injury in the testis. We evaluated here the effect of caffeic acid phenethyl ester (CAPE), a new antioxidant and anti-inflammatory agent on histopathological changes in testicular ischemia-reperfusion injury. Adult male Wistar rats were divided into six groups of five each: control group 1 (n=5), sham operation group 2 (n=5), torsion/detorsion (T/D) group 3 (n=5), T/D+saline group 4 (n=5), T/D+CAPE group 5 (n=5) and T/D+CAPE group 6 (n=5). Group 1 served to determine baseline values of histopathological parameters, group 2 animals that underwent sham operation served as a control, while groups 3-6 animals were subjected to left unilateral torsion (2 h) and detorsion (24 h) periods. All the groups were sacrified 24 h later except group 6. CAPE was injected 2 days with the same dose to the group 6 and it was sacrified 48 h later. One testis removed and fixed in Bouin's solution. After routine tissue processing myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) immunohistochemical methods were studied from paraffin embedded tissues. Treating rats with CAPE (applied at 10 micromol/kg, 30 min prior to T/D) attenuated the testicular injury and as well as the tissue levels of MPO. At the same time testis tissue showed a decrease in iNOS activity. Our results suggest that CAPE treatment have a protective role on testicular T/D and this effect may be due to inhibiting the neutrophil mediated cellular injury.

The protective role of erdosteine on testicular tissue after testicular torsion and detorsion

Testicular torsion and detorsion are important clinical problems for infertile man and oxidative stress may have a role in this clinical situation. The aim of this study was to investigate the protective role of erdosteine, an antioxidant, on unilateral testicular reperfusion injury in rats. The rats were divided into four groups including seven rats in each group: control, torsion, torsion/detorsion and torsion/detorsion+erdosteine. Rats, except the sham operation group, were subjected to left unilateral torsion (720( composite function) rotation in the clockwise direction) without including the epididymis. The experiments were finished after sham operation time for control, 120 min torsion for torsion group and 120 min torsion and 240 min detorsion for torsion/detorsion groups. Bilateral orchiectomy was performed for all groups of rats. The ipsilateral and controlateral testis were divided into two pieces to analyse biochemical parameters and to investigate the light microscopic view. Malondialdehyde level of ipsilateral testis was increased in torsion and torsion/detorsion groups in comparison with the other groups (p < 0.05). Erdosteine treatment ameliorated lipid peroxidation after torsion/detorsion in ipsilateral testis (p < 0.05). Also, xanthine oxidase activity of ipsilateral testis was increased in torsion/detorsion group in comparison with the others (p < 0.05). Nitric oxide (NO) level of ipsilateral testis was higher in all experimental groups than sham operated control group (p < 0.05). Also, NO level of torsion group was increased in comparison with detorsion groups (p < 0.05). Erdosteine treatment caused increased glutathione peroxidase activity in comparison with torsion and torsion/detorsion groups and catalase activity in comparison with the other groups in ipsilateral testis (p < 0.05). Superoxide dismutase activity of ipsilateral testis was higher in torsion/detorsion and torsion/detorsion+erdosteine groups than control and torsion groups (p < 0.05). The biochemical parameters were not affected in controlateral testis in all groups. Torsion, torsion/detorsion and torsion/detorsion+erdosteine groups showed ipsilateral testicular damage in the histological examination, but the specimens from torsion/detorsion had a significantly greater histological injury than those from the other groups (p < 0.05). Control rats showed normal seminiferous tubule morphology. Rats in torsion group had slight-to-moderate disruption of the seminiferous epithelium. Rats in torsion/detorsion group displayed moderate-to-severe disruption of the seminiferous epithelium. In all animals from torsion/detorsion+erdosteine group, the testicular tissues were affected with slight-to-moderate degenerative changes of the seminiferous epithelium. Administration of erdosteine resulted in a significantly reduced histological damage associated with torsion of the spermatic cord compared with torsion/detorsion. In all groups, the contralateral testes were histologically normal. In conclusion, the results clearly displayed that erdosteine treatment may have a protective role on testicular torsion/detorsion injury.

Melatonin reduces urinary excretion of N-acetyl-beta-D-glucosaminidase, albumin and renal oxidative markers in diabetic rats

1. Increased oxidative stress has an important role in the pathogenesis of diabetic nephropathy. The aim of the present study was to evaluate diabetic nephropathy by determining markers of oxidative stress and the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), albumin and to investigate the possible protective effects of in vivo melatonin on renal tubular oxidative damage in diabetic rats. 2. Twenty-six rats were randomly divided into three groups: (i) group I, control, non-diabetic rats (n = 9); (ii) group II, untreated diabetic rats (n = 8); and (iii) group III, melatonin-treated diabetic rats (n = 9). In groups II and III, diabetes developed 3 days after administration of a single dose of streptozotocin (35 mg/kg, i.p.). Thereafter, whereas the rats in group II received no treatment, rats in group III began to receive 10 mg/kg per day, i.p., melatonin for 8 weeks. Malondialdehyde (MDA), an index of lipid peroxidation, NAG and microalbumin in the urine, markers of renal tubular damage, were the parameters used for oxidative stress-induced renal injury. Superoxide dismutase (SOD), xanthine oxidase (XO) and glutathione peroxidase (GSH-Px) activities were determined to evaluate changes in the anti-oxidant status of kidney tissue. 3. In untreated diabetic rats, urinary NAG, albumin and renal MDA levels were markedly increased compared with control rats (P < 0.0001). However, these parameters were reduced in diabetic rats by melatonin treatment (P < 0.0001). Urinary excretion of NAG was positively correlated with the microalbuminuria and renal MDA levels (r = 0.8; P < 0.0001). The SOD and XO activities in the untreated diabetic group were found to be significantly higher than those of the control group (P < 0.0001). Superoxide dismutase and XO activities decreased in melatonin-treated rats compared with untreated diabetic rats (P < 0.002 and P < 0.023, respectively). However, the decrease did reach levels seen in control rats. There were no significant differences in GSH-Px activity between the three groups. 4. Therefore, on the basis of these data, we suggest that urinary NAG, albumin excretion, XO activity and MDA levels are more valuable parameters showing the degree of renal tubular injury than classical markers of oxidative stress, including SOD and GSH-Px, in diabetic rat kidneys. Melatonin has an ameliorating effect on oxidative stress-induced renal tubular damage via its anti-oxidant properties. Thus, it may be suggested that urinary NAG excretion and microalbuminuria may be important markers showing the degree of renal changes and the success of long-term treatment of renal impairment with melatonin.

Lithium-induced lung toxicity in rats: the effect of caffeic acid phenethyl ester (CAPE)

AIMS

We aimed to evaluate the effects of caffeic acid phenethyl ester (CAPE) on lithium (Li)-induced lung toxicity.

METHODS

Twenty-two adult male Wistar albino rats weighing between 280 and 300 g were used. The rats were randomly divided into three groups: control, Li and Li+CAPE groups. Li and CAPE were co-administered intraperitoneally twice daily for 4 weeks. Control rats were given 0.9% NaCl during the same period. All the rats were allowed to feed ad libitum until midnight after they had received the proposed treatment.

RESULTS

In the Li group, peribronchial and intraparenchymal lymphocyte and macrophage infiltration were observed. Atypical type II pneumocytes, alveolar destruction and emphysematous changes were also detected. Lymphocyte and macrophage infiltration was significantly decreased in the Li+CAPE group compared with the Li group. Alveolar destruction, emphysematous changes and intraparenchymal mononuclear cell infiltration were also recovered to a level close to the control group. Malondialdehyde (MDA) levels were increased in the Li group compared with the control group. CAPE administration decreased the MDA levels in the Li+CAPE group.

CONCLUSIONS

CAPE was found to associate with histopathological changes recovery in the lungs and oxidative stress due to Li treatment.

The effects of N-acetylcysteine on antioxidant enzyme activities in experimental testicular torsion

Testicular torsion is a serious problem in male children and, if not treated at the right time, can lead to subfertility and infertility. The main reason for testicular damage is ischemia-reperfusion injury. A number of chemical substances have been used to protect testes against ischemia-reperfusion injury in experimental animals. The possible protective effect of N-acetylcysteine on testicular tissue after testicular detorsion was examined in the current study. Twenty-four rats were divided into four groups: sham operation, torsion, detorsion, and NAC + detorsion groups (n = 6 for each group). Excluding sham operation group, the rats were subjected to unilateral torsion (720-degree rotation in clockwise direction). After torsion (5 h) and detorsion (2 h), unilateral orchidectomy was performed. Malondialdehyde levels and superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activities were determined in testicular tissue. Administration of N-acetylcysteine caused a decrease in malondialdehyde levels and an increase in glutathione peroxidase levels compared to detorsion group. The results suggest that N-acetylcysteine may be a potential protective agent for preventing the negative biochemical changes related to oxidative stress in testicular injury caused by testis torsion.

The activities of liver adenosine deaminase, xanthine oxidase, catalase, superoxide dismutase enzymes and the levels of malondialdehyde and nitric oxide after cisplatin toxicity in rats: protective effect of caffeic acid phenethyl ester

The aim of this experimental study was to investigate the effects of caffeic acid phenethyl ester (CAPE), an antioxidant agent, on cisplatin-induced hepatotoxicity through adenosine deaminase (AD), xanthine oxidase (XO), catalase (CAT), superoxide dismutase (SOD) activities and malondialdehyde (MDA) and nitric oxide (NO) levels in liver tissue of rats. Wistar albino rats were divided into three groups: control group (n = 6), cisplatin group (n = 9) and CAPE + cisplatin group (n = 8). All the chemicals used were applied intraperitoneally. Spectrophotometric methods were used to determine the activities of the above-mentioned enzymes in the liver tissue. NO level and XO activity were found to be increased in the cisplatin group compared to the control group. NO level was found to be decreased in the cisplatin + CAPE group in comparison with the cisplatin group. There was no significant change in the activity of XO between the cisplatin and cisplatin + CAPE groups. The activity of SOD was lower in the cisplatin group than both the control and cisplatin + CAPE groups. There was no significant change in the activity of CAT between the control and cisplatin groups. CAT activity was increased in the cisplatin + CAPE group compared to the cisplatin group. The AD activity and MDA level remained unchanged in all groups. The results obtained suggested that CAPE significantly attenuated the hepatotoxicity as an indirect target of cisplatin in an animal model of cisplatin-induced nephrotoxicity.

The activities of purine-catabolizing enzymes and the level of nitric oxide in rat kidneys subjected to methotrexate: Protective effect of caffeic acid phenethyl ester

The aim of this experimental study was to investigate the possible role of nitric oxide (NO) levels, and activities of adenosine deaminase (ADA) and xanthine oxidase (XO) in the pathogenesis of methotrexate-induced nephrotoxicity, and was the effect of caffeic acid phenethyl ester (CAPE), the potent free radical scavenger, in decreasing the toxicity. A total of 19 adult male rats were divided into three experimental groups, as follows: control group, MTX-treated group, and MTX+CAPE treated group. MTX were administered intraperitoneally (i.p.) with 20 mg/kg for single dose. CAPE was administered i.p. with a dose of 10 micromol//kg once daily for 7 days. The injection of MTX induced a significant increase in the activities of ADA and XO, and NO levels in renal tissue of rats (p < 0.0001). Co-treatment with CAPE caused a significantly decrease activities of ADA and XO, and the levels of NO in renal tissue (p < 0.0001). The results of this study revealed that NO, XO and ADA may play an important role in the pathogenesis of MTX-induced oxidative renal damage. CAPE may have protective potential in this process and it will become a promising drug in the prevention of this undesired side effect of MTX.